diff --git a/mesonbuild/interpreter.py b/mesonbuild/interpreter.py
index 63cdf9ea0..43ddd72a1 100644
--- a/mesonbuild/interpreter.py
+++ b/mesonbuild/interpreter.py
@@ -161,6 +161,7 @@ class ConfigurationDataHolder(MutableInterpreterObject):
                              'set_quoted': self.set_quoted_method,
                              'has': self.has_method,
                              'get': self.get_method,
+                             'merge_from': self.merge_from_method,
                              })
 
     def is_used(self):
@@ -221,6 +222,16 @@ class ConfigurationDataHolder(MutableInterpreterObject):
     def keys(self):
         return self.held_object.values.keys()
 
+    def merge_from_method(self, args, kwargs):
+        if len(args) != 1:
+            raise InterpreterException('Merge_from takes one positional argument.')
+        from_object = args[0]
+        if not isinstance(from_object, ConfigurationDataHolder):
+            raise InterpreterException('Merge_from argument must be a configuration data object.')
+        from_object = from_object.held_object
+        for k, v in from_object.values.items():
+            self.held_object.values[k] = v
+
 # Interpreter objects can not be pickled so we must have
 # these wrappers.
 
diff --git a/test cases/common/139 simd/meson.build b/test cases/common/139 simd/meson.build
index 2b7d722a6..d84b72248 100644
--- a/test cases/common/139 simd/meson.build	
+++ b/test cases/common/139 simd/meson.build	
@@ -4,6 +4,8 @@ simd = import('simd')
 
 cc = meson.get_compiler('c')
 
+cdata = configuration_data()
+
 if not meson.is_cross_build() and host_machine.cpu_family() == 'arm' and cc.get_id() == 'clang'
   message('Adding -march=armv7 because assuming that this build happens on Raspbian.')
   message('Its Clang seems to be misconfigured and does not support NEON by default.')
@@ -29,8 +31,7 @@ rval = simd.check('mysimds',
   compiler : cc)
 
 simdlibs = rval[0]
-# FIXME add cdata1.merge_from(cdata2)
-cdata = rval[1]
+cdata.merge_from(rval[1])
 
 configure_file(output : 'simdconfig.h',
   configuration : cdata)